WPP boss Sir Martin Sorrell on the Brexit: 'This is not good news, to say the least'

WPP founder and CEO Martin Sorrell speaks at the British chambers of Commerce annual conference in London Thomson Reuters Sir Martin Sorrell, the CEO of WPP — which is the world's advertising largest advertising holding company and based in the UK — has said Britain voting to leave the EU has left him "very disappointed."

In a statement sent to Business Insider minutes after a so-called "Brexit" was confirmed (which you can read in full below,) Sorrell laid out some of his immediate concerns.

He said: "Very disappointed, but the electorate has spoken. The resulting uncertainty, which will be considerable, will obviously slow decision-making and deter activity. This is not good news, to say the least. However, we must deploy that stiff upper lip and make the best of it."

Sorrell goes on to say that four of WPP's top 10 markets are in western continental Europe, so now the company must build its presence there even further. Those four are Germany (4), France (6), Italy (9), Spain (10).

He added: "It just underlines the importance of implementing our strategy: fast-growth markets (BRICs and Next 11), digital, data — and horizontality, which ironically means getting our people to work together, not apart!"

Martin SorrellGetty ImagesSorrell has long-said he wanted Britain to stay in the European Union.

At the company's AGM earlier this month, Sorrell said: "Obviously we have plans to deal with it but it would have a serious impact, we think, in the short-to-medium-term for the prospects of the company in western continental Europe. What it means is we will have to add jobs, not necessarily in the UK, but in those markets."

Meanwhile, Maurice Levy, the CEO of Publicis Groupe, a competing advertising agency holding company based in France, told us in January: "It will be more damaging for the British companies than for the European companies because what will happen is they will not be able to close the borders in the UK and they may lose a lot of advantages that they already have."

Sir Martin Sorrell, WPP CEO's full Brexit reaction statement:

Very disappointed, but the electorate has spoken. The resulting uncertainty, which will be considerable, will obviously slow decision-making and deter activity. This is not good news, to say the least. However, we must deploy that stiff upper lip and make the best of it. Four of WPP's top ten markets are in Western Continental Europe and we must build our presence there even further. It just underlines the importance of implementing our strategy: fast-growth markets (BRICs and Next 11), digital, data - and horizontality, which ironically means getting our people to work together, not apart!